Revision a6a5349d17f2a5c37079826f1a1474c3d08c6b53 authored by Sage Weil on 13 April 2010, 21:07:07 UTC, committed by Sage Weil on 13 April 2010, 21:07:07 UTC
Use a separate class for ceph sockets to prevent lockdep confusion.
Because ceph sockets only get passed kernel pointers, there is no
dependency from sk_lock -> mmap_sem.  If we share the same class as other
sockets, lockdep detects a circular dependency from

	mmap_sem (page fault) -> fs mutex -> sk_lock -> mmap_sem

because dependencies are noted from both ceph and user contexts.  Using
a separate class prevents the sk_lock(ceph) -> mmap_sem dependency and
makes lockdep happy.

Signed-off-by: Sage Weil <sage@newdream.net>
1 parent e1e4dd0
Raw File
rtmutex-debug.h
/*
 * RT-Mutexes: blocking mutual exclusion locks with PI support
 *
 * started by Ingo Molnar and Thomas Gleixner:
 *
 *  Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 *  Copyright (C) 2006, Timesys Corp., Thomas Gleixner <tglx@timesys.com>
 *
 * This file contains macros used solely by rtmutex.c. Debug version.
 */

extern void
rt_mutex_deadlock_account_lock(struct rt_mutex *lock, struct task_struct *task);
extern void rt_mutex_deadlock_account_unlock(struct task_struct *task);
extern void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
extern void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter);
extern void debug_rt_mutex_init(struct rt_mutex *lock, const char *name);
extern void debug_rt_mutex_lock(struct rt_mutex *lock);
extern void debug_rt_mutex_unlock(struct rt_mutex *lock);
extern void debug_rt_mutex_proxy_lock(struct rt_mutex *lock,
				      struct task_struct *powner);
extern void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock);
extern void debug_rt_mutex_deadlock(int detect, struct rt_mutex_waiter *waiter,
				    struct rt_mutex *lock);
extern void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter);
# define debug_rt_mutex_reset_waiter(w)			\
	do { (w)->deadlock_lock = NULL; } while (0)

static inline int debug_rt_mutex_detect_deadlock(struct rt_mutex_waiter *waiter,
						 int detect)
{
	return (waiter != NULL);
}
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